Squeezable dispensing devices for dispensing flowable materials are well known and such devices have heretofore been developed and/or utilized wherein bladder containment and/or pressure dispensing are shown. Such arrangements, for example, are described in U.S. Pat. No. 3,225,967 issued Dec. 28, 1965 to J. Heimgartner and U.S. Pat. No. 3,270,920 issued Sept. 6, 1966 to C. G. Nessler showing an arrangement wherein the contents of a bladder are urged therefrom by a supply of gas and which makes use of valves to modulate the expulsion of the contents from the bladder.
Another arrangement making use of a bladder containing materials to be dispensed by pressure is shown in U.S. Pat. No. 4,469,250 issued Sept. 4, 1984 to Evezich (the Applicant herein). In this arrangement a separate bladder is housed within a squeezable outer shell having a removable cap and nozzle construction and requiring a projection positioned at the base of the nozzle for piercing the bladder to allow dispensing of its contents, the various elements not being permanently affixed to one another.
Dispensing devices have also heretofore been known and/or utilized wherein an inflatable bladder is utilized to push contents out of a container (see for example U.S. Pat. No. 3,592,365), as have devices utilizing volume reducing structures for selectively changing the volume of the dispensing device (see for example U.S. Pat. Nos. 2,715,981, 3,474,936, 4,098,434, and 4,147,278).
While dispensing devices making use of bladders and/or pressure dispensing have heretofore been suggested and/or utilized, further improvements could nevertheless still be utilized.